The present invention relates to a lifter for lifting subterranean, vegetation products, such as, for example, potatoes, celery roots, carrots, bulbs, edible onions, etc., with the lifter comprising an in ground, under the products, driven cutting member and a conveyor positioned behind the cutting member for upwardly guiding the vegetation products.
A lifter of the aforementioned type may be used just to lift the vegetation products such as potatoes from the underground and lay the same on the ground or to lift the potatoes from there or directly from underground to a silo member and directly to a further preparing apparatus or device.
A disadvantage of conventional lifters resides in the fact that a certain percentage of the lifted potatoes are bruised or directly damaged thereby resulting in a loss of weight of the damaged potatoes during storage. Bruised potatoes having bruise marks, aside from not presenting an appealing appearance also result in a larger waste when peeled. An additional expense is also incurred when the stored potatoes are sprayed to protect the damaged potatoes against attacks from, for example, fungi.
The aim underlying the present invention essentially resides in providing a lifter which not only is as efficient as conventional harvesters but also reduces the amount of damage to the vegetation products being harvested.
In accordance with this present invention, a drive mechanism is provided which is capable of driving the moving parts of the potato lifter to achieve an optimum performance of the lifter.
Advantageously, in accordance with the present invention, a lifter is provided for lifting subterranean vegetation products such as, for example, potatoes, celery roots, carrots, bulbs, edible onions, etc., with the lifter including an in ground under the products driven cutting member and a conveyor positioned behind the cutting member for an upward guiding of the products. At least one substantially plain smooth surface delivery roll is provided and positioned between a rear edge of the cutting member and the conveyor.
In accordance with further features of the present invention, the delivery rollers are rotatably positioned about a substantially horizontal axis and are disposed in close proximity to each other and mutually parallel.
The delivery rolls are, in accordance with the present invention, driven by a drive means from at least one lifter supporting wheel through a gear transmission means, preferably being driven with such a velocity that the circumference of the delivery rolls is such that the foremost of the delivery rolls rotates with a circumferential velocity which is slightly greater than a monetary drive velocity of the potato lifter over the ground, and a rear most of the delivery rolls has the greatest circumferential velocity, with the delivery rolls between the first or foremost delivery roll and last delivery roll respectively having increasing higher circumferential velocities in proportion to the preceding delivery roll.
In accordance with the present invention, all of the delivery rolls have the same outer diameter and lengths of the delivery rolls are such that they extend from side to side within the lifter and corresponds to a width of the ribbon of earth being treated by the lifter.
Additionally, in accordance with the present invention, over at least a portion of the delivery rolls, an aiding or assisting conveyor carrying protruding and, preferably, yielding spikes is provided, whereby a lower side of the aiding conveyor, facing the delivery rolls, serves as an accompanying conveyor for the lifted products.
In accordance with still further features of the present invention, supporting means are provided for the aiding conveyor and are adjustable so as to provide for a predetermined spacing between the aiding conveyor and the delivery rolls.
Advantageously, the working surface of the conveyor disposed downstream of the delivery rolls in proportion to the upper conveying surface of the delivery rolls is situated relatively lower, respectively, that the level difference therebetween is adjustable by adjustable means.
By virtue of the provision of a vegetation products lifter in accordance with the present invention a surprisingly effective handling of vegetation products such as, for example, potatoes is attained. This is true even when lifting the potato up from the underground, as lifting them up from the surface of the ground after they by the same machine or by other means have been removed from underground and lay free on the surface of the ground for a suitable time period, as a part of preparing process, depending on the type of potatoes and local conditions, to let the potatoes be exposed to the surrounding free atmosphere before they are finally lifted by the potato lifter for storing in, for example, a silo or for further preparation. By lifting directly from the surface of the ground, it is advantageous to employ an upper aiding conveyor positioned above the delivery rollers, as the handling of the potatoes then is even more careful. Such an upper aiding conveyor is not utilized when lifting the potatoes from the underground. The addition of the aiding conveyor is thus an optional means which becomes operational when lifting potatoes directly from the ground.
Even the provision of a single delivery roll according to the invention introduces a positive effect. Generally three or four such delivery rollers positioned in parallel between the cutting member and a usually employed conveyor for the further transportation of the potatoes may be considered as an optimal combination.
Actual use of the lifter of the present invention has established a very considerable reduction of the percentage of damaged potatoes when compared with conventional lifters by, for example, a factor of reduction by 3 to 10 times. This applies in case of light as well as of heavy earth substance also when the potatoes are removed from a weedy ground surface. Moreover, the lifter is capable of being more successfully operated in a rain soaked soil than conventional harvesters. The lifter of the present invention is also capable of being successfully operated at a higher drive speed than conventional lifters.
The delivery rolls according to the present invention are advantageously arranged to be driven at different rotational speeds, with the speed of rotation being highest for the delivery rolls positioned farthest behind the cutting member. Hereby partly it is attained that, for example, small stones, lifted together with potatoes, are less apt to be stuck between the delivery rolls, which delivery rolls are substantially disposed in a mutually parallel position with a rotational axis thereof being disposed perpendicular to the drive direction of the lifter. For the use at very sloped fields the orientation of the rolls within the lifter may be adjustable, respectively, so that each delivery roll is divided into groups of, for example, three rolls, the axes of which are adjustable within a plane rectangular to the drive direction of the lifter. The delivery rolls within the lifter advantageously have the same external diameter, and a rotational speed of the rearmost delivery roll is 5 to 10% greater than a foremost delivery roll.
A forerunning guide wheel with side members to run on both sides of a row of growing potatoes, serving to guide the cutting member and the potato lifter, may advantageously also be employed at the lifter according to the invention.
The above and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in connection with the accompanying drawings which show, for the purposes of illustration only, one embodiment in accordance with the present invention.